کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1404427 1501902 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Structure and optical properties of porous silicon prepared on thin epitaxial silicon layer on silicon substrates
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Structure and optical properties of porous silicon prepared on thin epitaxial silicon layer on silicon substrates
چکیده انگلیسی
Porous silicon (PSi) samples were prepared by electrochemical etching of silicon-on-insulator wafers, consisting of 45 μm thick p-type (111) silicon epitaxial layer grown on a thin 100 nm SiO2 layer on silicon substrates, by varying the concentration of 48% HF in ethanol solution. Within the epitaxial layer micro- and nano-sized pores of different sizes in dependence on HF concentration were obtained. The structural and optical properties of prepared samples were investigated by Raman spectroscopy, infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). SEM images showed high density of micrometer sized pores whose morphology and density depend on the HF concentration. Nanometer sized silicon structures were observed by phonon confinement effects of TO and TA phonon bands in the Raman spectra. The broadening of crystalline silicon (c-Si) vibrational band at 520 cm−1, that indicates phonon confinement, increased with decreasing the HF concentration. At the same time the TA-like phonon vibrational band at 150 cm−1, that characterizes the short range confinement, also appeared in same samples. All samples showed photoluminescence (PL) peak in visible spectral range. The change in intensity and position of the PL peak showed strong sensitivity to the influence of different environment conditions; air, vacuum and acetone.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure - Volumes 834–836, 27 May 2007, Pages 465-470
نویسندگان
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